Automatic switching mechanism.



F. A. LUNDQUIST. AUTOMATIC SWITCHING MECHANISM.

APPLICATION FILED AUG-16,1916.

Patented Jan. ,8, 1918'.

hive/#01: E an/r A. Lundquisz I 6 y W Affy UNITED STATES PATENT OFFICE.

FRANK A. LUNDQUIST, OF NEW YORK, N. Y., ASSIGNOR T0 WESTERN ELECTRIC COIVI- PANY, INCORPORATED, 013 NEW YORK, N. Y., A CORPORATION OF NEW YORK.

AUTOMATIC SWITCHING MECHANISM.

Specification of Letters Patent.

Patented Jan. s, 1918.

Application filed August 16, 1916. Serial No. 115,178

To all whom it may concern:

Be it known that I, FRANK A. LUNDQUIST, a citizen of the United States, residing at New York, in the county of New York and State of New York, have invented certain new and useful Improvements in Automatic Switching Mechanism, of which the following is a full, clear, concise, and exact description.

This invention relates to automatic switches of the panel type, and has for its objects certain improvements in the structure and operation of a switch of this type, whereby units of large capacity and with the minimum number of operating parts may be conveniently constructed and operated.

One of the features of this invention relates to the construction of the switch,

whereby the contacts constituting one bank of terminals may be spaced twice as far apart as in the switches of this type previously constructed, without increasing the distance over which the contacting brushes have to move between the first and last contact. In accordance with this feature of the invention, the terminals constituting a bank are mounted in parallel rows with the terminals of one row staggered with respect to the terminals of another row, and brushes are provided which are adapted to travel freely between the rows of terminals without engagement therewith, but which may be swung in either direction into engagement with selected ones of said terminals.

According to another feature of this invention, the movement of a set of brushes to a selected contact bank is under control of a single magnet which also controls the release of the brush carriage to bring it into operation. In accordance with this feature, there is provided arotatable and vertically movable shaft adapted iii one posi-- tion to release a selected brush carriage, and in succeeding rotated positions, dependent upon the number 'of banks to which the brush carriage is common, to select the bank containing the terminals with which the brushes are to connect. After the'selection of the bank by the rotation of the shaft, it is moved vertically step by step to bring the brushes into position to engage the selected terminals in the bank. The movement of the brush carriage in selecting a terminal bank will be in steps of a length equal to the width of a bank, while the steps for bringing the brushes into positionto engage V the terminals in the bank will be in steps equal to the vertical distance between terminals of adjacent rows.

Other features of the invention relate to the provision and mounting of test terminals and cooperating brushes and other details looking to the simplification of the structure and operation of the switch.

In the drawings, Figure lis a diagram matic view of circuits and mechanism of a switch embodying the features of this invention Fig. 2 is a fragmentary View of the alternative scheme for swinging the brush carriage into engagement with a selected terminal; Fig. 3 is a view in front elevation Y of a terminal bank showing the method of mounting the terminals and the relation of the brushes thereto when the device is used in connection with a threewire circuit; Fig.

4 is a View in front elevation of a terminal bank illustrating a method of mounting the terminals and brushes for use of the device in a two-wire circuit; and Fig. 5 is a View. showing part of the restoring mechanism of the device.

Referring to the drawings, and particularly to Fig. 1, 5 designates a rotatably and vertically movable shaft. Secured to said shaft is a ratchet wheel 6 adapted to be engaged by a pawl 7 controlled by an electromagnet 8 to rotate said shaft. Carried upon the shaft 5 above the ratchet wheel 6 is an escapement rack comprising teeth 10, adapted to cooperate with an escapement. pawl 11 controlled by an electromagnet 12 to permit the step-by-step movement of said mounted upon a second shaft 15, extending parallel to the shaft 5, are a plurality of brush carriages 16, 16. The brush carriages 16, 16 are adapted to move by gravity along 100 the shaft 15, under control of the shaft 5, but are normally retained against such movement by means of a latch member 18, individual to each of said brush carriages.

Mounted upon each of the carriages 16, 16 105 the shaft 15, are adapted to rotate through a 110 device shown in Fig. 1 and illustrating an shaft 5 in a downward direction. Slidably displacement of the shaft 15. vPreferably,

the shaft 15 is made square in cross-section for this purpose. Means, either electromagnetic as shown in Fig. 1, or mechanical as shown in Fig, 2, are provided to displace the shaft 15 either to right or left for purposes of making contact between certain of the brushes and selected terminals in a bank, as will be more fully explained hereinafter.

Assuming now that the switch is to operate in connection with a three-wire circuit, there will of course be three brushes and three terminals for each position of thebrush carriage away from normal. In Fig. 3', there is shown a scheme of mounting the terminals for a three-wire circuit. In this figure there are shown a plurality of terminals, 30, 30-31, 31-32, 324-23, 334.4, 34 and 35, 35. These terminals are mounted in'pairs and in vertically arranged parallel rows'in the bank, all of the terminals 30 and 31 being pair d to 'form one row, 32 and 33 paired to form another row and the terminals 34 and 35 paired to form a third row. -The terminals 30 and 31, which are paired to form one row, have the separate terminals of each pair staggered with respect to each other in the direction of movement of the brushes. The same relation exists between the separate terminals 32 and 33, and 34 and 35 of the other two rows. Also the pairs of terminals of each are in astaggered relation to the pairs in the other rows. That is, the terminals 30 and 31, beginning at the top of the row, are higher 1n the bank than the first pair comprised of the terminals 32 and 33, which latter terminals are higher in the bank than the top pair 34 and 35 of the third row. The terminals 31, 31 and 34, 34 of the two outside rows form thetest terminals and are adapted to be wiped by the brushes 22 and 23 in the. movement of the brush carriage 16. The brushes 22 and 23 are so mounted that they will not engage their respective terminals simultaneously. The terminals 30, 32, 33 and 35 may constitute the terminals of talking'lines in a telephone exchange equipment, and in the structure shown the terminals 30 and 32 would be in one circuit while 33 and 35 would be in another circuit.

The brushes 20 and 21 of the sets are mounted in a staggered relation to each other, corresponding with the staggering of the pairs of contacts of adjacent rows of terminals and are adapted normally to pass between the rows of terminals without engagement therewith. These brushes 20 and 21 are adapted, however, as the shaft 15 is angularly displaced either to the left or the right, to engage terminals 30 and 32 or terminals 33 and 35 to close the corresponding circuits.

As shown in the drawings, the shaft 5 has mounted upon it a plurality of pairs of radially extending arms 40, 41 and 40, 41, one for each brush carriage 16, the arm 40 being located directly above 41, and a plurality of sets of radially arranged arms 42, 43', 44, the number of these arms in a set corresponding to the number of contact banks in the switch to which a brush carriage 16 is common, the arms 42, 43, 44, etc., of each set being arranged spirally, back of the arms 41 41, etc., of the same set.

lteferring now to the operation of the device it will be assumed that the switch is to be operated to connect the brushes 20' and 21 of the uppermost brush carriage 16 with the fourth set of contacts-in the first bank. The impulses for doing this will come over line wire 50, through an impulse relay 51 which, upon its first energization, completes a circuit .for a slow-release relay 52, the armature of which remains attracted during the sending of a particular set of pulses. The first set of-pulses will be for the purpose-of operating the magnet S to rotate the. shaft 5 into position, where the uppermost arm 40 will be directly over an arm 53 on the latch 18 of the uppermost brush carriage 16. The current pulses for operating the magnet 8 will be from battery 54, through normal contact 55 of relay 51, alternate contact 56 of slow-release relay 52, switch arm 57, contact 58 and magnet 8 to ground. There will also be a branch circuit from battery 54, through a slow-release magnet 59 controlling an escapement 60 to which are attached switch arms 57and 61. Upon the first cnergization of the magnet 8, the pawl 7 is brought into engagement with the ratchet wheel 6 to rotate the shaft 5 one step, and a contact 62 is closed for completing a circuit through a slow-release magnet 63. The slow-release magnet 63, upon energization, releases a pawl 64 from a collar 65 on the lower end of the shaft 5, and draws -a pawl 66 into position to engage said collar without any downward movement of the shaft 5. The magnet 63, being slow to release, will hold the shaft in this position during the sending of the impulses through the magnet 8 for rotating the shaft 5 into the desired position. As the pawl 7 moves inwardly on the first stepping impulse, a projection 67 thereon will engage one arm of a bell crank lever 68, to disengage the other arm thereof from a pivotal holding pawl 69, which is caused to swing inwardly into engagement with the ratchet wheel 7, thereby holding the shaft 5 in its rotated position. When the stepping impulses over the line have ceased, the line relay 51 will hold up, thus opening the circuit through the slow-release magnet 59 and also'through the stepping magnet 8 at its hen magnet 59 re normal contact V leases its armature, the. escapement 60 1s arms 57 and 61 from their first into their second positions. When the stepping impulses throughthe magnet 8 have ceased, its armature will drop back, opening the contact 62 and thereby causing the denergization of the magnet 63 to withdraw the pawl 66 and permit the shaft 5 to drop until the lowermost projection 10 of the escapement rack engages the pawl 11. This downward movement of the shaft 5 causes the arm 40 to engage the arm 53 of the latch 18, and releases the brush carriage 16, whereupon it will drop until the arm 53 strikes and rests on the projecting arm 41 on the shaft 5 which is directly below the arm- 40. The next step will be to rotate the shaft 5 until the arm opposite the bank containing the desired terminals is in position to catch the brush carriage 16. In the case of the particular selection assumed, the terminals sought are in the first bank which is opposite the arm 42, and it will require one impulse to move the arm 42 into position to stop the downward movement of the brush carriage 16 which will be released from the arm 4-1 by the second rotation ofthe shaft 5. The impulse for this will be over the line 50,

as previously described, and the slow-release magnet 59, operates the escapement to move the switch arms 57 and 61 into their third position. In the third position of the switch arms 57 and 61, the arm 57 transfers the impulse circuit from the rotary magnet 8 to the vertical magnet 12, and since the brush carriage 16 is now resting on the arm 42, four impulses over the line circuit will operate the escapement 10-11 to drop the shaft 5 and brush carriage 16 into position where the brushes 20 and 21 will be in position to engage the fourth set of contacts in the first bank. As the shaft 5 moves downward, in response to the impulses through the magnet 12, a wiper 70 thereon will wipe over contacts 71, 71, alternate ones of which are connected together to form a set, one of said sets being connected in circuit with a magnet 7 2, and the other of said sets being in circuit with a magnet 73, which magnets are located adjacent the upper end of the shaft 15, and are adapted, when energized, to attract a common armature 74 to swing said shaftq15 to the right or to the left. At the end of the four; impulses through the magnet 12, the sending circuit will again be interrupted at the sending station, and the magnet 59 again .deenergizes to operate the escapement 60 to move the arms 57 and 61 into their fourth and final position. In this position the switch arm 61 completes a circuit which may be traced from battery at 75, through switch arm 61, conductor 76, the wiper 7 O, the fourth one of the contacts 71, conductor 77 and magnet 72 to ground. The energization of the magnet 72 swings the shaft 15 to the right, looking at the face of the contact bank as in Fig. 3, and engages the brushes 20 and 21 with the fourth set of terminals in that bank.

So long as the line 50 is in use the line relay 51 will remain energized, as will also the slow-release relay 52. As soon, however, as the line 50 is opened, relays 51 and 52 will drop off their armatures and thus close a circuit through a restoring magnet 80, which may be traced from battery at 54 through the normal contacts of relays .51 and 52, conductor 81, contacts 82 closed by the first downward movement of the shaft 5, and magnet 80. The energization of the magnet attracts its armature 83. to throw out holding and stepping pawls 84 and 85 of the ,escapement 59, thereby'permittingit to return to normal under actlon of a spring (not shown), As the escapement 60 returns to normal, switch arm 61 opens the circuit through the magnet 72, thereby permitting shaft 15 to restore to its neutral position and disengage the brushes 20 and 21 from their contacts. The attraction of the armature 83 of the magnet 80 releases a pawl 86, which permits a drum 87 to engage a clutch member 88 on a constantly rotating shaft 89, thereby to rotate the drum 87 and wind up a tape 90, carrying lugs 91 and 92. The lug 91 engages an arm 93 on the shaft 5 to raise said-shaft while the lug 92 engages with the arm of the latch 18 to restore the brush carriage 16 to normal or latching position. As the shaft 5 approaches its uppermost. position, it opens the contacts 82, thereby breaking the circuit of magnet 80. At the same time a collar 95on the shaft 5 engages the pawl 86 to move it into latching engagement with the armature 83. There being no current through the magnet 63, the pawl 64 will engage the collar 65 to retain the shaft 5 in its normal vertical position. A collar 96 on the shaft 5 is adapted when the said shaft 5 is moved upward to engage the holdin paWl 69 and swing it away from the rate et wheel 6 and into locking engagement with the bell crank lever 68.

As soon as holding pawl 69 is released from ratchet wheel 6, the shaft 5 will be rotated to normal position by means of spring driven gear 97, which mesheswith a feathered gear 98 on the upper end of the said shaft 5.

Had the terminals to be selected been in another of the banks to which the selected brush carriage is common, it would have been dropped into selectiye position with respect to this bank by bringing the corresponding arm 43, 44, 45 or 46, as the case may be, into the pathof movement of the arm 53. 'The selection of the terminals in the bank will then be accomplished by the V In the modification shown in Fig. 2, the shaft 5 is provided with a notched rack '100 operating in conjunction with a swinging lever arm 101 to determine the direction in which the shaft will be displaced. A pivotal T-shaped member 102, having one end in engagement with a pin 103, projecting from the shaft 15, is adapted to be engaged at its free ends by a pivotal operating member 104: operated upon the denergization of a slow-release magnet 105, controlled over a circuit in parallel with the stepping magnet 12. Durlng the stepping of the shaft 5 l by the magnet 12, a pivotal arm 106 is lifted by'the energization of the slow-release magnet 105 to hold the operating member 104 out of engagement with the T-shaped member 102. When, however, the stepping impulses cease, the arm 106 drops, and either the right-hand end or the left-hand end of the operating member 104 will engage the corresponding end of. the T-shaped member 102, depending upon whether the lower end of the lever 101is resting in a notch of the rack 10001' upon a high portion of the said' rack between notches, thereby swinging the shaft 15 either to theright or the left.

When the switch is used with two-wire circuits and the test terminal is not required,

the terminals and brushes may be arranged as shown in Fig. 4. In this view, the terminals of one circuit are shown mounted in pairs, one vertically above the other, and in two rows, the pairs of terminals in one row being staggered with respect to the pairs of terminals in the other row. The brushes are arranged to engage the terminals flatwise when the shaft is angularly displaced.

What is claimed is: 1. In a switching mechanism, a contact bank comprising a plurality of stationary contact terminals mounted in parallel rows, a movable contact arranged to be moved between the rows of said stationary terminals without engagement therewith until opposite a selected terminal, and means for then moving said movable contact into engagement with a selected terminal of either of the rows of the bank between which said movable contact is arranged to be moved.

2. In a switching mechanism, a contact bank comprising aaplurality of stationary contact terminals mounted in parallel rows, the terminals of one row being mounted in staggered relation with respect to the contacts of another row, a set of step-by-step movable contact members adapted to travel between the rows of stationary terminals without engagement therewith, and means for swinging said movable contact members into engagement with selected ones of said stationary terminals.

3. In a switching mechanism, a bank of contact terminals comprising a plurality of parallel vertical rows, the terminals in one row being vertically staggered with respect to the terminal of another row, movable brushes, means for moving said brushes step by step between the rows of terminals in steps equal to the vertical distance between vertically adjacent terminals of adjacent rows without engagement therewith, and means for swinging said brushes into engagement with a selected set of said stationary terminals.

4. In a switching mechanism, a bank of contact terminals comprising a plurality of parallel vertical rows, the terminals in one row being vertically staggered with respect to the terminals of another row, movably mounted brushes adapted to travel between the two rows of contacts without engagement therewith, step-by-step mechanism adapted to move said brushes in steps equal to the vertical distance between vertically adjacent terminals of adjacent rows, means for swinging said brushes in either direction to engage selected terminals of a bank, and means controlled by said step-by-step mechanism for determining the direction in which said brushes will be swung.

5. In a switching mechanism, a bank of contacts comprising a plurality of parallel vertical rows, two terminals in one row being vertically staggered with respect to the terminals of another row, movable brushes adapted to travel between the two rows of contacts without engagement therewith, a vertically movable shaft operated to move said brushes in steps each equal to the vertical distance between vertically adjacent terminalsof adjacent rows, means for angularly displacing said brushes to the right or left to bring them into engagement with selected terminals in the bank, and means controlled in the movement of said shaft to determine the direction in which said brushes will be displaced.

6. In a switching mechanism, a plurality of banks each comprising a plurality of contact terminals, a set of brushes common to a plurality of said banks, a movable brush carriage for said brushes, a rotatable and vertically movable shaft, means controlled in the rotation of said shaft to select a brush' of banks each comprising a plurality of contact terminals, a set of brushes common to a plurality of said banks, a gravity-operated brush carriage for said'brushes, means for normally holding said brush carriage in an elevated position, a rotatable and vertically movable shaft, means on 'said shaft adapted in the rotationthereof to be moved into position to trip said brush carriage, a plurality of spirally arranged arms on said shaft adapted to be separately moved into the path of movement of said brush carria e to arrest its movement before a selected ba and means for dropping said shaft step by step to cause the selection of contact terminals in said bank.

9. In a telephone switching mechanism, a contact bank comprising a plurality-of parallel rows of vertically arranged contacts, the contacts of each row being mounted in pairs with the individual contacts of each row in staggered relation to each other and the pairs of contacts of one row being vertically staggered with respect to the contacts of the other row, the correspondingly staggel-ed pairs in adjacent rows being connected with the same circuit, a plurality of movable brushes adapted to pass between the contacts of a plurality of rows without engagement therewith, and means for swing- 111g said brushes into engagement with corresponding contacts of adjacent' rows.

10. In a telephone switching mechanism, a contact bank comprising three parallel rows of vertically arranged contacts, the contacts of each row being mounted in pairs with the individual contacts of each row in staggered relation to each other, and the pairs of contacts of each row being vertically staggered with respect to the pairs of contacts of the other rows, the correspondingly staggered terminals of the pairs in adjacent rows being connected with the same c'ircuit'and the outside terminals of the outer rows being projected beyond the other terminals of the bank and adapted for test purposes, a brush carriage, a pair of brushes thereon adapted to move between the middle and two outside rows of terminals without engagement therewith, a second pair of' brushes adapted to engage the terminals of the outside rows in the movement of said brush carriage, and means for swinging said 7 first pair of brushes into engagement with corresponding contacts of adjacent rows. 1

11. In an automatic switch, a plurality of contacts, a brush to cooperate with said contacts, a support, a plurality of stop members carried thereby, means for initiating the travel of said brush, and means operable during said travel for operating said support to position one of said stop members to arrest the travel of said brush on a desired one of said'contacts.

In witness whereof I hereunto subscribe my name this 15th day of August, A. D. 1916.

FRANK A. LUNDQUIST. 

